Tabor 8020, Руководство пользователя

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5-6. SPECIAL HANDLING OF STATIC SENSITIVE
DEVICES
MOS devices are designed to operate at a very high imped-
ance levels for low power consumption. As a result, any
normnal static charge that builds up on your person or
clothing may be sufficient to destroy these devices if they
are not handled properly. When handling such devices, use
precautions which are described in the following to avoid
damaging them.
1 . The MOS ICs should be transported and handled only
in containers specially designed to prevent static build-up.
Typically, these parts will be received in static-protected
containers of plastic or foam. Keep these devices in their
original containers until ready for installation.
2 . Remove the devices from the protective containers only
at a properly grounded work station. Also ground yourself
with a suitable wrist strap.
3 . Remove the devices only by the body; do not touch the
pins.
4 . Any printed circuit board into which the device is to be
inserted must also be grounded to the bench or table. 5 .
Use only anti-static type solder sucker.
6 . Use only grounded soldering irons.
7 . Once the device is installed on the PC board, the device
is normally adequately protected, and normal handling
resume.
5-7. CLEANING
Model 8020 should be cleaned as often as operating con-
dition require. Thoroughly clean the inside and the outside
of the instrument. Remove dust from inaccessible areas
with low pressure compressed air or vacuum cleaner. Use
alcohol applied with a cleaning brush to remove accumu-
lation of dirt or grease from connector contacts and com-
ponent terminals.
Clean the exterior of the instrument and the front panel
with a mild detergent mixed with water, applying the
solution with a soft, lint-free cloth
5-8. REPAIR AND REPLACEMENT
Repair and replacement of electrical and mechanical parts
must be accomplished with great care and caution. Printed
circuit boards can become warped, cracked or burnt from
exessive heat or mechnical stress. The following repair
techniques are suggested to avoid inadverant destruction
or degradation of parts and assemblies.
Use ordinary 60/40 solder and 35 to 40 watt pencil type
soldering iron on the circuit board. The tip of the iron
should be clean and properly tinned for best heat transfer
to the solder joint. A higher wattage soldering iron may
separate the circuit from the base material. Keep the sol-
dering iron in contact with the PC board for a minimum
time to avoid damage to the components or printed con-
ductors.
To desolder components use a commercial “solder
sipper”, or better, solder removing SOLDER - WICK, size
3. Always replace a component with its exact duplicate as
specified in the parts list.
5-9. PERFORMANCE CHECKS
The following performance checks verify proper operation
of the instrument, and should normally be used:
1 . As part of incoming inspection of instrument specifica-
tions;
2 . As part of troubleshooting procedure;
3 . After any repair or adjustment, before returning instru-
ment to regular service.
5-9-1. Environmental Conditions
Tests should be performed under labortory conditions hav-
ing an ambient temperature of 25 +/-5 deg C and a relative
humidity of less than 80%. If the instrument has been
subjected to conditions outside these ranges, allow at least
one additional hour for the instrument to stabilize before
beginning the adjustment procedure.
5-9-2. Warm-Up Period
Most equipment is subject to at least a small amount of drift
when it is first turned on. To ensure accuracy, turn on the
power to the Model 8020 and allow it to warm-up for at
least 30 minutes before beginning the performance tests
procedure.
5-9-3. Recommended Test Equipment
Recommended test equipment for troubleshooting, cali-
bration and performance checking is listed in table 5-2.
Test instruments other than those listed may be used only
if their specifications equal or exceed the required charac-
teristics.
Model 8020 Maintenance And Performance Tests
Page 5-3